In recent years, display devices such as liquid crystal displays and organic electroluminescent display devices are used in various fields. As the base material for display devices, for example, a resin film is adopted. Here, such a technique is conventionally known that, for example, after stacking a functional layer such as a liquid crystal layer or a light-emitting layer on a resin film, a resin film medium is cut by a punching blade or a laser beam in order to obtain a resin film medium of a target size.